[Bug regression/60363] [4.9 Regression]: logical_op_short_circuit, gcc.dg/tree-ssa/ssa-dom-thread-4.c scan-tree-dump-times dom1 "Threaded" 4

[amker.cheng at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60363

--- Comment #3 from bin.cheng <amker.cheng at gmail dot com> ---
After patching 208165, there are two more jump threading opportunities for dom1
pass.  Jump threading is doing alright, the interesting thing is why there is
no such opportunities before patching.

I attatched related dump files with/without patch.  It seems dumps before vrp1
pass are pretty similar, while after vrp1, dump with patch shows the two
additional jump threading opportunities.  In other words, they are somehow
already fixed (not introduced) in pass vrp1 without patching.

For now I can just change ssa-dom-thread-4.c to handle the two jump threadings,
or should I look into vrp to find the difference in the first place?